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The patient has a compensated (PCO2 should be 1.5(HCO3) +8 for compensation which it is) anion gap (AG=32=Na-(Cl+HCO3)) metabolic acidosis and with signs of intoxication.

The next step is to measure the plasma osmolality and compare it to the estimated osmolality which is 287; (2Na+(BUN/2.8)+(glucose/18)+(blood ethanol/4.6)) to determine the osmolar gap (measured osmolality-calculated osmolality=osmolar gap) which, in normal cases, is less than 10 so a higher gap is due to low molecular weight molecules such as ethylene glycol, methanol, acetone, ketones that are not accounted for in the equation.

Methanol is used in paint thinners and is a likely culprit in this case.

Ketoacidosis is a cause of anion gap metabolic acidosis, but given the normal blood glucose in this case, it is unlikely.

Pohanka M, Toxicology and the biological role of methanol and ethanol: Current view. Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia. 2016 Mar [PubMed PMID: 26006090]